Now, when you search someone's email address, the results will not only show messages from them but some extra info about that contact. You'll see their contact photo, as well as links to email them, IM them, call them using Gmail calling, and video chat with them. If they're on Google+, you'll also see what circle they're in, and this information will stay up to date as they change it on their profile. It's a small change, but a bit quicker than opening up the contacts page and searching for them there.

The new update adds better circles integration into Gmail as well. Not everyone is seeing it yet, but it should roll out to all Gmail users by the end of the day. If it's popped up for you, let us know what you think in the comments.